The invention relates generally to sockets for retaining card edge memory modules and, more particularly, to a high reliability socket for memory modules.
Computers and servers may use numerous types of electronic modules, such as processor and memory modules (e.g. Dynamic Random Access Memory (DRAM), Synchronous Dynamic Random Access Memory (SDRAM), or Extended Data Out Random Access Memory (EDO RAM), an the like). The modules are produced in a number of formats such as, for example, Single In-line Memory Modules (SIMM's), or the newer Dual In-line Memory Modules (DIMM's) and Fully Buffered DIMM's.
Typically, the modules are installed in one or more multi-pin sockets mounted on a system board or motherboard. Each module has a card edge that provides an interface generally between two rows of contacts in the socket. Conventionally, the card edge interface is a separable card edge interface. These card edge interfaces, however, are generally not high reliability interfaces and therefore do not meet requirements for some high end server applications. For example, card edge interfaces may fail when subjected to shock and vibration which may occur, for instance, during shipping, loading and unloading. End wall towers and latching mechanisms on the sockets are particularly susceptible to failure from vibration. Further, high insertion forces and mating forces can deflect the card sufficiently to damage components on the card.
One commonly used approach for increasing reliability is to directly attach the module via an inseparable interface. This is sometimes done when it is desirable that the end user not be able to remove processors or memory modules from the system so that problems that might arise from reconfiguration of the system do not occur. The provision of a high reliability interface that meets the requirements for high end systems and applications remains difficult.